Needle clamping device for sewing machines



April 7, 1936. y C F, RUBEL 2,036,959

NEEDLE CLAMPING DEVICE FOR SEWING MACHINES Filed Dec. l, 1935 Patented Apr. 7, 1936 UNITED STATES NEEDLE CLAMPING DEVICE FOR SEWING MACHINES Charles F. Rubel, Chicago, Ill., assignor to Union Special Machine Company, Chicago, Ill., a corporation of Illinois ,Application December 1, 1933, Serial No. 700,589

2 Claims.

The present invention relates to improve-- ments in devices for clamping the needle of a sewing machine to the needle bar, and more particularly to an improved needle clamping device which consists of a minimum number of parts; which is inexpensive to manufacture, easy to assemble and extremely durable.

An object of the present invention is to provide an improved needle clamping device. wherein a collar member carrying a single setscrew is adapted to be placed on the lower end of the needle bar and wherein the set-screw is adapted to hold a needle in position and to support the collar in position against an abutment on the needle bar whereby no additional securing member is necessary so-that the assembly consists of a minimum number of parts.

The above and other objects of the invention will in part be obvious and will be hereinafter more fully pointed out.

In the drawing:

Figure 1 is an elevation showing the assembled needle and needle clamping device on a needle bar.

Fig. 2 is a side view of Fig. l.

Fig. 3 is a view, similar to` Fig. 1, but partly in section to show the arrangement of the various parts and the details of construction.

Fig. 4 is a sectional view taken along the line 4--4 of Fig. 1.

Fig. 5 is a View taken along the line 5 5 of Fig. 3.

Referring to the accompanying drawing, there is illustrated a needle bar I8, which is adapted to reciprocate within the head of a sewing machine (not shown) in the usual manner. The needle bar Ill is provided, at the lower end thereof, with. a reduced end portion II, thereby aiording a horizontal shoulder or abutment I2, which extends around the needlebar at the point Where the reduced portion II joins the. body portion thereof. The reduced end portion II is provided with a vertical recess I3 which communicates with a horizontal recess I4 which extends laterally into the needle bar to a point slightly beyond the central axis thereof. The horizontal axis of the recess I4 is substantially in line with the horizontal abutment I2 on the needle bar I8. Intermediate the ends of the reduced portion II, there is provided an opening I5 which extends through the annular wall of the reduced portion II and thus communicates with the vertical recess I3 therein. A collar member I6 is adapted to iit over the reduced end II o-f the needle bar with the upper surface thereof engaging the horizontal shoulder i2. This collar carries an integral depending arm I'I which has a laterally extending portion I8. The laterally extending portion I8 has an opening I9 with which a slot 2B communicates whereby to form a substantially forked end on the portion I8. A set screw 2l is adapted to extend through a hole in the collar I6 and to threadedly engage the same. The screw 2l is provided with a reduced end portion 22 which is adapted to pass through the opening I 5 in the wall of the reduced end II of the needle bar I8. It will thus be apparent that the shoulder abutment I2 on the needle bar II) serves as a means for properly positioning the collar I6 on the end II of the needle vbar IU so that when the collar is fitted thereon, the end 22 of the screw 2I will be in exact alignment with the opening I5 in the needle Ibar. A needle 23 is then inserted through thev opening I9 in the laterally extending portion I8 with the shank 23a thereof passing through the vertical recess I3 in the lower end of the needle bar. The screw' 2i is then turned so that the end 22 thereof will pass through the opening I5 and engage the shank 23a, of the needle 23 and thus clamp the same firmly against the opposite portion of the wall of the reduced end Il of the needle bar and at the same time clamp the opposite face of the collar I6 against the end II. 'I'he reduced end 22 of the screw 2I in the opening I5 will prevent the collar I6 from descending on the needle bar so that the entire assembly is held on by a single screw 2| which also serves to hold the needle 23 in place. The laterally extending p0rtion I8 of the arm I1 serves as a thread guide. The thread is passed through the slot 20 so that it will be led from the take-up mechanism to a point in close proximity to the shank of the needle and thence down to the eye of the needle. The upper end of the needle shank 23a is curved and fits snugly against the curved surface of the opening I4. It is diicult to drill the vertical recessv I3 to an exact depth within close limits to provide a bearing surface for the upper end of the needle and it is for this reason that there is provided the horizontal recess I4 which intersects the vertical recess. Thus, it will be noted that the upper surface of the recess I4 affords a stop whereby the needle 23 may be inserted into the needle bar I8 to a fixed depth and also affords an accurate bearing surface for the end 23a thereof.

It will be noted, from the foregoing description, that an extremely simple and efficient device for clamping the needle of a sewing machine to the needle bar is herewith provided. The device consists of a few parts so that they may be of rugged construction. Relatively coarse threads may be employed in the screw and collar in order to increase the strength and durability of the device since there is no threaded engagement of the screw with the needle bar. The shoulder I2 serves as a convenient means for positioning the collar on the needle bar so that the small end of the screw will pass through the opening l5 to clamp the needle.

It is to be clearly understood that minor changes may be made in the details of construction and arrangement of parts without departing from the scope of the invention as set forth in the appended claims.

What I claim as new and desire to secure by Letters Patent, isz- 1. The combination with a needle bar having a reduced end portion, a vertical recess extending upwardly through said reduced end portion, a horizontal shoulder around the needle bar at the point where the reduced end portion thereof joins the body portion thereof, a horizontal recess extending laterally into said needle bar and intersecting said vertical recess, and an opening through the wall of said reduced end portion, of a needle having the shank thereof inserted in said vertical recess with the upper end bearing against the surface of said horizontal recess, of a collar member having a threaded horizontal recess, said collar member being adapted to be fitted over said reduced end portion with the upper face thereof abutting against said shoulder whereby to position the threaded recess therein in axial alignment with the opening in the Wall of said reduced end portion, and of a screw member adapted to threadedly engage the threaded recess in said collar member and having a reduced end adapted to extend through the opening in the wall of the reduced end portion of the needle bar whereby to clamp the needle and the collar member in position.

. 2. The combination with a needle bar having a reduced end portion, a vertical recess extending upwardly through said reduced end portion, a horizontal shoulder around the needle bar at the point where the reduced end portion thereof joins the body portion thereof, a horizontal recess extending laterally into said needle bar and intersecting said vertical recess, and an opening through the wall of said reduced end portion, of a needle having the shank thereof inserted in said vertical recess with the upper end bearing against the surface of said horizontal recess, of a collar member having a threaded horizontal recess, and an integral thread guide' depending therefrom and encircling the needle whereby to lead the thread in close proximity to the shank of the needle, said collar member being adapted to be fitted over said reduced end portion with the upper face thereof abutting against said shoulder whereby to position the threaded recess therein in axial alignment with the opening in the wall of said reduced end portion, and of a screw member adapted to threadedly engage the threaded recess in said collar member and having a reduced end adapted to extend through the opening in the wall of the reduced end portion of the needle bar whereby to clamprthe needle and the collar member in position.

CHARLES F. RUBEL. 

